#box {
    width: 300px;
    height: 50px;
    background: lightblue;
    margin: 100px auto;
}

button {
    margin: 0 auto;
    display: block;
}

.enter {
    transform: translateX(-100%);
    opacity: 0;
}

.enter-active {
    transform: translateX(0);
    opacity: 1;

    transition: all 1s ease;
}

.enter-done {
    border: 5px solid #000;
}

.exit {
    transform: translateX(0%);
    opacity: 1;
}

.exit-active {
    transform: translateX(100%);
    opacity: 0;

    transition: all 1s ease;
}

.exit-done {}

.appear {
    transform: scale(0);
}

.appear-active {
    transform: scale(1);
    transition: all 1s ease;
}

.appear-done {}